Setting up rblsmtpd

NB: you can skip this page if you decided to use qmail-dnsbl instead


A Realtime Blackhole List (RBL) is a list of addresses that an RBL list supplier believes are a source of Spam.
rblsmtpd blocks mail from RBL-listed sites. It works with any SMTP server that can run under tcpserver.

qmail-smtpd's run script is already set to run rblsmtpd before qmail-smtpd. The following lines are related to rblsmtpd (others are omitted):

# This enables greetdelay anti-spam functionality on rblsmtpd
export GREETDELAY=15

# This disables rblsmtpd reject
#export RBLSMTPD=""

exec /usr/local/bin/softlimit -m "$SOFTLIMIT" \
    /usr/local/bin/tcpserver -v -H -R -l 0 \
    -x /home/vpopmail/etc/tcp.smtp.cdb -c "$MAXSMTPD" \
    -u "$QMAILDUID" -g "$NOFILESGID" 0 25 \
    /usr/local/bin/rblsmtpd -W \
        -b -r zen.spamhaus.org \
-r bl.spamcop.org \
 /var/qmail/bin/qmail-smtpd 2>&1

Since rblsmtpd is the first program who talks with the sender you may want to enable the GREETDELAY here and not inside qmail-smtpd. GREETDELAY=15 sets a delay of 15 seconds. In this example two different RBL sources will be queried. If their responce is ok the qmail-smtpd program will be run.

To disable rblsmtpd you have to delete the following lines from the code above:

/usr/local/bin/rblsmtpd -W \
        -b -r zen.spamhaus.org \
 -b -r bl.spamcop.org \

NB: If you decide to use zen.spamhaus.org as suggested here, check the free use terms and be aware that exceeding these terms causes the cut off of your server. I think that one of my servers has been banned, since I can't resolve  zen.spamhaus.org.

Testing spamhaus.org

Connect to Russel Nelson's http://www.crynwr.com/spam/ site and follow the instructions. In a few words you have to do a telnet ns1.crynwr.com from your mail server and look if spamhaus.org is working fine as a filter.

Howto avoid being "cut off" by spamhaus.org

You may be interested at this point to take a look to the idea of Costel Balta, which is addressed to decrease the amount of connections to the RBL lists, avoiding to be banned consequently.

Comments

HI!

This text is awesome!

I have only one question

Is there any place where i can change the annoying rblsmtpd.local? that's the text appearing in SMTP GREETING 220 rblsmtpd.local.

Thanks in advance
 

you have to modify rblsmtpd.c at line 201/203 and recompile. It should be quite easy to build a patch that reads the control/me file and use its contents as the rblsmtpd helo..

Thanks Man! I did it and it works great!

I made some modifications in order to use other Antivirus and the speed of the services is awesome.

Thanks again!

Hi Enetcs and All,

We have qmail server version [qmail-toaster-1.03-1.3.22] installed. This installation and configuration has been made by some one else/x colleague.

We are dealing problem of receiving spam mail.  In /var/qmail/contrl/blacklist file having only one entry i.e. -r zen.spamhaus.org. Spamassian version is spamassassin-toaster-3.3.2-1.4.3.

Can you guide me how to stop or atleast decrease the frequency of receiving spam mail?

Thanks in advance.